A University of Arizona researcher wants to study the effects of pot on US combat veterans with PTSD.Medical marijuana is legal in Arizona but the problem the researcher says, is government red tape that’s holding her back.

The downtown UA Phoenix Medical Campus psychiatrist says thousands of veterans return from overseas who suffer with the mental disorder. But Dr. Sue Sisley says there’s virtually no research on how marijuana could help with their symptoms.

CBS 5 obtained the research proposal authored by Sisley.

"We’re specifically looking at how effective marijuana is in treating combat vets," she said.

A University of Arizona review board and the Food and Drug Administration gave her the green light to conduct the study in 2011. But the National Institute on Drug Abuse still hasn’t authorized it.

"NIDA will not fund any research whose goal is to find benefits of medical marijuana," said Dr. Richard Strand with the Arizona Wellness Chamber of Commerce. Strand says the NIDA is the only federal organization that cultivates marijuana for legal research.

"It’s in the pipeline waiting in limbo until we can persuade NIDA to sell us the study drug and the DEA to give us a permit so we’re allowed to store the drug on campus," said Sisley.

Strand says American universities are losing the global competition in this kind of research.

"If medical schools are forbidden from doing this, we’re really missing out in advances in medical science," he said.

Reviewers from the Health and Human Services Department blocking Sisley at this point say there was substantial concern over this study and its use of "drug naive" participants.

Sisley says if her school and the FDA are behind it, then it should be a no brainer.

"They felt this is going to provide critical information to the medical community and health care in general."

Sisley says she hopes to introduce a bill in Congress that will allow these kinds of studies to happen.